The Iraq war has already cost the United States $320bn (£180bn), according to an authoritative new report, and even if a troop withdrawal begins this year, the conflict is set to be more expensive in real terms than the Vietnam War, a generation ago.

The estimate, circulated this week by the non-partisan Congressional Research Service (CRS), can only increase unease over the US presence in Iraq, whose direct costs now run at some $6bn a month, or $200m a day, with no end in sight.

The Bush administration has refused to provide any specific overall figure for the war's cost. But the Senate is set to approve another emergency spending bill in May, meaning that Iraq will have consumed $101bn in fiscal 2006 alone, almost double the $51bn of 2003, the year of the invasion itself - and all at a time when the federal budget deficit is running at near record levels.

Blog editor's note: Robert Scheer is one of this country's best national security journalists, in my view. His new book should be fascinating reading.

With over 65 percent of Americans disapproving of our current president, why can't we get some credible opposition in Washington? As we head towards midterm elections, and look ahead to those of 2008, it's a question that is weighing heavily on millions of American minds.

Two longtime observers of our increasingly corrupt political system, Robert Scheer and Joe Klein have written books documenting the causes and the consequences. After 30 years covering politics, Scheer and Klein have some startling insights.

In conversation with AlterNet, Scheer explains why he thinks Nixon was one of the great policymakers of our time. Come back Monday to see Klein discuss how we can tell when politicians mean what they say. While Klein and Scheer have a distinctly different set of politics, you'll be surprised at their unified call for reform -- and a cause that progressives can rally behind.

Robert Scheer spent over 30 years interviewing American presidents and candidates since Nixon, but it was only in retrospect that he discovered a disturbing pattern. Scheer's new book Playing President: My Close Encounters with Nixon, Carter, Bush I, Reagan and Clinton -- and How They Did Not Prepare Me for George W. Bush explores the crippling effects the campaign process had on every candidate he interviewed -- and how our presidents have become increasingly out of touch with American voters.